2022 年 11 巻 1 号 p. 7-15
Research has been conducted to speed up and simplify the 90Sr analysis method in water samples based on the importance of 90Sr measurement for environmental monitoring in the event of a radiological incident. To optimize the measurement with ICP-MS, which enables rapid analysis, we examined the pre-treatment conditions when cation exchange resin chromatography and Sr Resin solid-phase extraction were used. Sr was quantitatively recovered by cation exchange resin from 1 L synthetic water samples, and anionic components such as Ge and Se were efficiently removed. In addition, under the elution condition using 3 M HNO3, it is possible to suppress the elution of Zr with a small volume of eluent. The eluate from cation exchange chromatography can be used for successive solid-phase extraction of Sr-Resin directly, which provides further Sr purification and concentration sufficient for 90Sr determination by ICP-MS. Verification was performed on real samples including high hardness bottled water. We confirmed that the results of the synthetic sample analysis were reproduced, and that Sr was quantitatively recovered (96-100%) and coexisting elements were removed sufficiently so as not to interfere with the measurement of 90Sr. 90Sr was concentrated by a factor of 100 during chemical separation procedure without any evaporation step. Processing time for more than 10 samples was 3 hours, which is fast enough for emergency response in the case of radiological incident.
